Paliperidone is chemically known as 3-[2-[4-(6-fluoro-1,2-benzisoxazol-3-yl)-1-piperidinyl]ethyl]-6,7,8,9-tetrahydro-9-hydroxy-2-methyl-4Hpyrido[1,2-a]pyrimidin-4-one, is a 5-HT antagonist and belonging to the chemical class of benzisoxazole derivatives and having the following structural formula:

Paliperidone (“PLP”) is a metabolite of Risperidone. Marketed under the trade name Invega, Paliperidone is an anti-psychotropic agent approved in the United States for the treatment of schizophrenia.
The Palmitate ester of Paliperidone can be chemically named as 3-[2-[4-(6-fluoro-1,2-benzoisoxazol-3-yl)-1-piperidyl]ethyl]-6,7,8,9-tetrahydro-9-hydroxy-2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one Palmitate ester and has the following formula:

Paliperidone Palmitate (“PLP-P”) is described in U.S. Pat. Nos. 5,158,952 and 5,254,556. US '556 disclose processes for the preparation of both the decanoyl and the acetyl derivatives of Paliperidone Palmitate.
Other process for the preparation of PLP-P are described in U.S. Pat. No. 6,077,843 and US Patent Application No. 20080214808.